Meningitis Caused by Extensively Drug-Resistant Acinetobacter baumannii: Treatment Options and Factors Affecting Outcomes

Meningitis Caused by Extensively Drug-Resistant Acinetobacter baumannii: Treatment Options and Factors Affecting Outcomes | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Meningitis Caused by Extensively Drug-Resistant Acinetobacter baumannii: Treatment Options and Factors Affecting Outcomes Fatih Temoçin, Tuba Kuruoglu, Sümeyra Nur Erbaş, Tuba Sena Karaçeşme, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6165448/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Introduction In this study, we analyzed the clinical features of nosocomial meningitis caused by Acinetobacter baumannii ( A. baumannii ) to identify the factors affecting the outcome and compared the effectiveness of different therapeutic regimens. Methods The study analyzed patients diagnosed with healthcare-associated meningitis due to A. baumannii, and cases between 2017 and 2022 were included. Results We analyzed data from 52 patients. The 14-day mortality rate was 26.9%, and the 28-day mortality rate was 42.3%. Univariate analysis of factors affecting mortality showed that patients who did not receive intraventricular (IVT) treatment had a 5.6-fold higher risk of 14-day mortality and a 5.3-fold higher risk of 28-day mortality. In these patients, the higher risk of 14-day and 28-day mortality was also confirmed by the results of the multivariate analysis [p = 0.032, OR: 15.341; p = 0.039, OR: 9.273, respectively]. Whereas 10 of 26 patients (38.4%) who received only intravenous (IV) treatment achieved microbiological cure, 20 of 26 patients (76.9%) who received IV + IVT treatment achieved microbiological cure, and the difference was statistically significant (p = 0.005). There were no differences in 14-day and 28-day mortality rates between patients who received IVT colistin or amikacin in addition to IV therapy (p = 0.51, p = 0.63, respectively). Conclusion Our findings showed that adding IVT colistin or amikacin to IV therapy significantly decreases mortality and increases the microbiological cure. Acinetobacter baumannii nosocomial meningitis intraventricular treatment intrathecal treatment healthcare-associated meningitis Introduction One of the most important complications after neurosurgery operations is central nervous system (CNS) infections. Gram-positive cocci are the most common pathogens, while gram-negative bacteria cause approximately 15% of CNS infections [ 1 , 2 ]. Acinetobacter baumannii ( A. baumannii ) is the most common pathogen of healthcare-associated gram-negative bacterial meningitis [ 3 – 5 ]. In the absence of appropriate treatment, the mortality rate of affected patients can be pretty high (15–70%). An increased infection rate caused by the strains of MDR- A. baumannii has recently been reported [ 6 , 7 ]. Treating infections caused by multi-drug-resistant (MDR) and extensively drug-resistant (XDR) strains of bacteria has become extremely difficult. Although multidrug-resistant strains of A. baumannii are a global concern, studies on nosocomial meningitis cases caused by A. baumannii are limited. The options for treating patients with meningitis caused by A. baumannii are extremely limited because the choice of antibiotic depends not only on the sensitivity of the pathogen to the antibiotic but also on the penetration of the selected antibiotic through the blood-brain barrier. Therefore, to treat meningitis caused by A. baumannii, intrathecal (ITH) or intraventricular (IVT) antibiotics should be administered along with intravenous antibiotics. In this study, we analyzed the clinical features of nosocomial meningitis caused by A. baumannii to identify the factors affecting the outcome, compare the effectiveness of different therapeutic regimens, and determine the antimicrobial resistance rates of the pathogen. Materials and methods We conducted a single-center retrospective study in a large regional hospital affiliated with Ondokuz Mayis University, Faculty of Medicine, Infectious Diseases, and Neurosurgery clinics. Our hospital is located in the Black Sea region of Turkey and has 110 third-level intensive care beds, with a total bed capacity of 1,100. The study included meningitis patients caused by A.baumannii for 2017–2022. The data were collected from archives of infectious diseases, the neurosurgery clinic, and the digital archives of the hospital. Meningitis diagnosis criteria were defined according to the Centers for Disease Control and Prevention (CDC) [ 8 ]. Inclusion criteria; Patients with at least 2 of the following signs or symptoms with no other recognized cause: headache, dizziness, fever (> 38°C), localizing neurologic signs, changing level of consciousness, or confusion A. baumannii growth in cerebrospinal fluid (CSF) culture Increased white cells, elevated protein, and/or decreased glucose in CSF The following patients were excluded from the study: Patients under 18 years of age Patients with polymicrobial growth in the CSF culture Patients receiving treatment for less than 48 h Patients with hematological malignancies Isolations of Acinetobacter species other than A. baumannii Patients with another concomitant nosocomial infection Patients for whom demographic data, medical history, and treatment data were missing This study was approved by the Ethical Committee of Ondokuz Mayis University and the Administrative Council of the Faculty of Medicine (Grant No.: 2022/426). Epidemiological data Besides recording the data on the demographic characteristics of the patients, we also recorded the underlying diseases, whether the patient underwent cranial surgery, the number of cranial surgeries, time to diagnosis of meningitis after surgery, number of days hospitalized before diagnosis, prior use of antibiotics, the results of the cerebrospinal fluid (CSF) microbiological and biochemical analysis at diagnosis, blood culture at diagnosis, white blood cell count, CRP and procalcitonin values, fever at the time of diagnosis, hypotension, and Glasgow coma scale (GCS) score, treatments administered for meningitis and, treatment responses. Prior use of antibiotics was defined as a treatment for at least 48 h during the 10 days before the diagnosis of meningitis. The antibiotic resistance profile of the pathogenic microorganism was also recorded and analyzed. Microbiological analysis All CSF samples were analyzed in our center's microbiology laboratory. The antimicrobial susceptibilty of the isolates was determined by VITEK® 2 Compakt (bioMérieux, Inc., Marcy l'Etoile, France) automated system. Acinetobacter baumannii was identified by the automated Matrix-Assisted Laser Desorption Ionization-Time of Flight (MALDI-TOF) Mass Spectrometry system (Vitek MS® systems, bioMérieux, Inc., Marcy l'Etoile, France). The in-vitro antibiotic susceptibility of the isolates was determined based on the European Committee on Antimicrobial Susceptibility Testing (EUCAST) criteria. Colistin susceptibility testing was performed using 96-well broth microdilution (BMD) panels following EUCAST recommendations. According to EUCAST criteria, isolates with a colistin minimum inhibitory concentration (MIC) of > 2 µg/mL were considered resistant. Treatment and cure The treatment choice and route of administration are at the treating clinician's discretion. No other protocol was used for the study. Following the initial diagnosis of meningitis, treatment consisted of the following parenterally administered antibiotics, used either as monotherapy or in combination therapy: meropenem 2 g/8 h as a 3-hour extended infusion, amikacin 500 mg/12 h, ampicillin/sulbactam 3 g/8 h, tigecycline (100 mg IV initially, followed by 50 mg/12 h), and colistin sulfomethate sodium 5 mg/kg/day in three divided doses. Antibiotic doses were adjusted according to the patient's renal function. Intraventricular treatments included colistin (polymyxin E) methanesulfonate (12,500 IU = 1 mg) 10 mg/day, or amikacin 30 mg/day. Intravenous antibiotics were classified as appropriate or inappropriate based on the microbiological activity against A. baumannii . If the IV regimen included at least one microbiologically active agent, it was classified as an appropriate treatment. Conversely, the treatment was classified as inappropriate if none of the administered IV antibiotics were active against the pathogen. Patients were followed until hospital death or discharge. Treatment response was assessed by 14-day and 28-day mortality. The microbiological cure was accepted as no growth in CSF control cultures performed after at least 48 hours of treatment. Use of Artificial Intelligence During the preparation of this manuscript, artificial intelligence (AI)-assisted technology (ChatGPT-Model o1) was used solely for language editing and writing improvement. Statistical analysis The data were analyzed using IBM SPSS V23. The Kolmogorov-Smirnov and Shapiro-Wilk tests were conducted to determine whether the data followed a normal distribution. Binary logistic regression analysis was performed to examine the mortality risk factors on days 14 and 28. The enter method was used to include the independent variables in the model. The results of the analyses were presented as frequency (percentage) for categorical variables and mean ± standard deviation for quantitative variables. All differences were considered to be statistically significant at p < 0.05. Results We analyzed data of those patients (n = 52) who met the inclusion criteria. Among the participants, 24 were male, and 28 were female; their mean age was 54.5 ± 16.9 years. We found that 33 patients (63.5%) were hospitalized in the intensive care unit, and 19 (36.5%) were hospitalized in the neurosurgery and infectious diseases service. The mean number of days of hospitalization was 22.9 ± 15.2. Also, 48 patients had various neurosurgical interventions, and four had no neurosurgery or procedure. The most common neurosurgical diagnosis was spontaneous intracranial hemorrhage. Moreover, 50% of the patients had a history of external ventricular drainage, and 28.8% had a history of craniotomy. Comorbid conditions were present in 67.3% of the patients. The most common comorbid condition was hypertension, affecting 48.1% of the patients. A. baumannii was also detected in the blood cultures of 17.3% of the patients. The 14-day mortality rate was 26.9%, and the 28-day mortality rate was 42.3%. The demographic data and the clinical and laboratory characteristics of the participants are presented in Table 1 . Table 1 Demographic data and the clinical and laboratory characteristics No. of patients n.52 Percentage % Gender(M/F) 24/28 46.2/53.8 Age (mean ± Std. deviation) 54.5 ± 16.9 Fever at diagnosis 29 55.8 Hypotension at diagnosis 14 26.9 Charlson Comorbidity Index [median (min-max)] 3 (0–11) Comorbidities 35 67.3 Diabetes mellitus 12 23.1 Hypertension 25 48.1 Pulmonary diseases 2 3.8 Inpatient clinic Intensive care unit* 33 63.5 Wards 19 36.5 Day of hospitalization (mean ± Std.Deviation) 22.9 ± 15.2 Primary neurosurgical diagnose Spontaneous intracranial hemorrhage 35 67.3 Traumatic head injury 6 11.5 Brain tumor 4 7.7 Hydrocephalus 2 3.8 No neurosurgical diagnose 5 9.6 Neurosurgical history Craniotomy 15 28.8 External ventricular drainage 26 50 Ventriculoperitoneal shunt 4 7.7 Cerebral embolisation 3 5.8 No neurosurgical history 4 7.7 Number of neurosurgery [median (min-max)] 2 (0–8) Laboratory findings [mean ± Std.Deviation (min-max)] Blood WBC (count/uL) 13802.5 ± 6863.1 (2990–36060) Blood CRP (mg/L) 125.1 ± 112 (2-385) Blood Procalcitonin (ng/mL) 8.2 ± 10.8 (0.2–86.3) Cerebrospinal fluid leukocyte (count/mm 3 ) 855 ± 104 (0-10000) Cerebrospinal fluid glucose (mg/dL) 55.1 ± 43 (1-143) Cerebrospinal fluid protein (mg/dL) 253 ± 310 (6-1138) Positive blood culture for A. baumannii 9 17.3 Clinical outcome 14-day mortality 14 26.9 28-day mortality 22 42.3 Microbiologic cure 30 57.7 * ICU admission for at least 48 hours during the entire hospital stay. A total of 26 patients (50%) received only intravenous (IV) antibiotics, while the remaining 26 patients (50%) received both IV and intraventricular (IVT) antibiotics. Among those who received only IV therapy, the most commonly used regimen was meropenem plus colistin (17 patients, 65.3%), followed by meropenem monotherapy. In the IVT group, colistin was administered to 21 patients, and amikacin to 5. The most frequently used combination in the IVT group was IV meropenem + IV colistin + IVT colistin (14 patients). Detailed information on all administered treatments is provided in Table 2 . Table 2 Antibiotics used for the treatment of meningitis Treatment No. of patients n.52 Persentage % Only IV treatment 26 50 Meropenem + Colistin 17 65.3 Meropenem 7 26.9 Meropenem + Amikacin 1 3.8 Meropenem + Sulbactam ampicilin 1 3.8 IV plus Intraventricular treatment* 26 50 Meropenem + Colistin + Intraventricular Colistin 14 53.8 Meropenem + Colistin + Intraventricular Amikacin 1 3.8 Meropenem + Intraventricular Colistin 3 11.5 Meropenem + Intraventricular Amikacin 1 3.8 Meropenem + Amikacin + Intraventricular Amikacin 2 7.6 Meropenem + Amikacin + Intraventricular Colistin 3 11.5 Meropenem + Tigecycline + Intraventricular Amikacin 1 3.8 Colistin + Intraventricular Colistin 1 3.8 *Amikacin 30 mg/day and colistin (polymyxin E) methanesulfonate (12.500 IU = 1 mg) 10 mg/day were administered The univariate analysis of the factors affecting mortality showed that the 14-day mortality risk was 5.6 times, the 28-day mortality risk was 5.3 times higher for the patients who did not receive IVT treatment [p = 0.018, OR: 5.622 (1.342–23.559); p = 0.007, OR: 5.333 (1.595–17.829), respectively]. The higher risk of 14-day and 28-day mortality in those patients who did not receive IVT therapy was also confirmed by the results of the multivariate analysis [p = 0.032, OR: 15.341; p = 0.039, OR: 9.273, respectively]. While 10 of 26 patients (38.4%) who received only IV treatment achieved microbiological cure, 20 of 26 patients (76.9%) who received IV + IVT treatment achieved microbiological cure, and the difference was statistically significant (p = 0.005). For the 26 patients who received IVT therapy, the difference in their 14-day and 28-day mortality rates after colistin or amikacin was insignificant (p = 0.51, p = 0.63, respectively). Additionally, no chemical ventriculitis or catheter-related complications were detected in IVT treatment patients. In the univariate analysis, the blood procalcitonin values before treatment were significantly higher in the deceased patients [p = 0.03, OR: 1.026 (0.992–1.062)], but in the multivariate analysis, they were not significant. The age, gender, underlying chronic diseases, Charlson Comorbidity Index, pre-diagnostic antibiotic use, and the results of the CSF cytological and biochemical analysis of the mortality of the patients did not have a significant effect. The examined risk factors affecting the 14-day and 28-day mortality are shown in Tables 3 and 4 . Our analysis included the diagnoses of spontaneous intracranial hemorrhage, head trauma, brain tumor, and hydrocephalus, which are thought to predispose patients to develop meningitis. However, no statistically significant associations were found between these diagnoses and 14- or 28-day mortality (p = 0.27, p = 0.84, respectively). Table 3 Analysis of the risk factors affecting the 14-day mortality, determined by binary logistic regression analysis Characteristics Outcome Univariate Multivariate analysis Survived(n = 38) Dead(n = 14) P value OR (%95 CI) P value OR (%95 CI) Gender (Female/Male) 20/18 8/6 0.77 0.833 (0.242–2.866) 0.447 0.442 (0.054–3.627) Age (mean ± Std.Deviation) 53.61 ± 16.21 57 ± 19.08 0.52 1.012 (0.975–1.051) 0.548 0..923 (0.892–1.130) Fever at diagnosis (Yes/No) 20/18 9/5 0.46 1.620 (0.457–5.741) 0.755 0.715 (0.088–5.848) Hypotension at diagnosis (Yes/No) 10/28 4/10 0.87 1.120 (0.286–4.390) 0.465 0.462 (0.058–3.660) Glaskow Coma Scale [Median (min-max)] 8(3–15) 10(3–15) 0.22 1.107 (0.942–1.3) 0.332 1.178 (0.846–1.640) Charlson Comorbidity Index [Median (min-max)] 3 (0–9) 3 (0–11) 0.490 1.093 (0.849–1.406) 0.643 1.105 (0.725–1.682) Frequency of neurosurgery 2(0–8) 1(0–8) 0.83 1.039 (0.733–1.474) 0.151 1.423 (0.879–2.306) Stay before the diagnosis (mean ± Std.Deviation) 11.29 ± 10.51 11.25 ± 9.33 0.642 0.99 (0.949–1.033) - - ICU/Clinic ward 24/14 9/5 0.94 0.952 (0.266–3.414) 0.192 0.116 (0.005–2.936) Chronic Diseases (Yes/No) 27/11 8/6 0.35 1.841 (0.517–6.553) 0.213 0.139 (0.138–4.347) Diabetes Mellitus 8/30 4/9 0.48 0.6 (0.146–2.464) - - Hypertension 19/19 6/8 0.65 1.333 (0.388–4.584) - - Prior use of antibiotics (Yes/No) 23/15 6/8 0.26 2.044 (0.59–7.082) 0.525 1.872 (0.271–12.951) Laboratory findings at the time of diagnosis (mean ± Std.Deviation) Cerebrospinal fluid leukocyte (count/mm3) 427.89 ± 660.62 2014.29 ± 3623.26 0.078 1 (1–1.001) - - Cerebrospinal fluid glucose (mg/dL) 54.21 ± 40.08 57.69 ± 51.69 0.8 1.002 (0.987–1.017) 0.351 0.823 (0.753–1.108) Cerebrospinal fluid protein (mg/dL) 165.35 ± 249.83 205.77 ± 345.78 0.435 1 (0.998–1.003) 0.686 1.001 (0.998–1.004) Blood CRP (mg/L) 118 ± 109.57 154.84 ± 118.17 0.3 1.003 (0.997–1.008) - - Blood Procalcitonin (ng/mL) 4.73 ± 17.01 16.83 ± 27.29 0.03 1.026 (0.992–1.062) - - Blood WBC (count/uL) 13824.61 ± 6980.78 13740.71 ± 6788.74 0.97 1 (1–1) 0.385 1 (1–1) Intraventricular treatment (Yes/No) 23/15 3/11 0.02 5.622 (1.342–23.559) 0.032 15.341 (1.260–186.832) Appropriateness of treatment (Appropriate/Inappropriate)* 24/11 8/4 0.903 1.091 (0.270–4.408) 0.098 8.746(0.671-113.924) Cox & Snell R 2 = %25.1; Nagelkerke R 2 = %37.2 * Five patients were excluded from the analysis due to a lack of data on colistin susceptibility. Table 4 Analysis of risk factors affecting the 28-day mortality, determined by binary logistic regression analysis Characteristics Outcome Univariate Multivariate analysis Survived(n = 30) Dead(n = 22) P value OR (%95 CI) P value OR (%95 CI) Gender (Female/Male) 17/13 11/11 0.634 1.308 (0.433–3.946) 0.159 0.241 (0.033–1.744) Age (mean ± Std.Deviation) 54.57 ± 16.54 54.45 ± 17.77 0.981 1 (0.967–1.033) 0.932 0.943 (0.901–1.086) Fever at diagnosis (Yes/No) 15/15 14/8 0.33 1.750 (0.568–5.393) 0.935 0.924 (0.140–6.111) Hypotension at diagnosis (Yes/No) 6/24 8/14 0.194 2.286 (0.657–7.954) 0.130 0.229 (0.034–1.541) Glaskow Coma Scale [Median (min-max)] 8(3–15) 10(3–15) 0.128 1.122 (0.967–1.302) 0.265 1.184 (0.880–1.593) Charlson Comorbidity Index [Median (min-max)] 3 (0–9) 3 (1–11) 0.670 1.001 (0.625–1.049) 0.616 1.095 (0.768–1.560) Frequency of neurosurgery 2(0–8) 1(0–8) 0.395 0.86 (0.608–1.217) 0.835 1.049 (0.670–1.641) Stay before the diagnosis (mean ± Std.Deviation) 25.87 ± 15.23 19 ± 14.61 0.114 0.968 (0.929–1.008) - - ICU/Clinic ward 19/11 14/8 0.982 0.987 (0.315–3.095) 0.225 0.195 (0.012–3.248) Chronic Diseases (Yes/No) 20/10 15/7 0.908 0.933 (0.288–3.023) 0.298 0.041 (0.003–2.746) Diabetes Mellitus 5/25 8/14 0.174 0.4 (0.107–1.499) - - Hypertension 12/18 13/9 0.176 0.462 (0.15–1.415) - - Prior use of antibiotics (Yes/No) 18/12 11/11 0.474 1.5 (0.494–4.551) 0.609 0.625 (0.103–3.784) Laboratory findings at the time of diagnosis (mean ± Std.Deviation) Cerebrospinal fluid leukocyte (count/mm3) 467.33 ± 703.33 1383.64 ± 2988.52 0.175 1 (1–1.001) - - Cerebrospinal fluid glucose (mg/dL) 51.23 ± 36.22 60.05 ± 50.74 0.482 1.005 (0.991–1.019) 0.280 1.001 (0.971–1.047) Cerebrospinal fluid protein (mg/dL) 132.20 ± 193.24 232.70 ± 351.06 0.316 1.001 (0.999–1.003) 0.181 1.002 (0.999–1.006) Blood CRP (mg/L) 122.95 ± 113.6 134.93 ± 112.21 0.703 1.001 (0.996–1.006) - - Blood Procalcitonin (ng/mL) 5.79 ± 19.23 11.24 ± 22.96 0.043 2.013 (0.981–2.047) - - Blood WBC (count/uL) 14099.77 ± 7838.62 13396 ± 5407.68 0.713 1 (1–1) 0.534 1 (1–1) Intraventricular treatment (Yes/No) 20/10 6/16 0.007 5.333 (1.595–17.829) 0.039 9.273 (1.124–76.485) Appropriateness of treatment (Appropriate/Inappropriate)* 18/9 14/6 0.965 1.221 (0.733–3.25) 0.234 3.541 (0.441–28.469) Cox & Snell R 2 = %31.2; Nagelkerke R 2 = %41.7 *Five patients were excluded from the analysis due to a lack of data on colistin susceptibility. The meropenem resistance rate was 90.4%, and the colistin resistance rate was 12.8% for the 52 A. baumannii strains that were included in the study. The antibiotic resistance rates of the pathogen are presented in Table 5 . Evaluation of the microbiological activity of the intravenous treatments revealed that 32 patients received appropriate therapy, while 15 received inappropriate therapy. In five patients treated with colistin, the appropriateness of therapy could not be assessed due to the lack of data regarding the colistin susceptibility of A. baumannii . Although mortality was lower in the group that received appropriate therapy, no statistically significant differences were observed in the univariate or multivariate analyses (Tables 3 and 4 ). Table 5 Susceptibility of A. baumannii isolates n.52 Sensitive Resistance Resistance rate % Meropenem 5 47 90.4 Imipenem 5 47 90.4 Amikacin 18 34 65.4 Gentamicin 9 43 82.7 Colistin (n.39) 34 5 12.8 Trimethoprim-sulfamethoxazole 9 43 82.7 Ciprofloxacin (n.17) 4 13 76.5 Discussion In our study, the 14-day mortality rate due to all causes was 26.9%, and the 28-day mortality rate was 42.3%. The mortality rates of patients with meningitis due to A. baumannii vary between 15% and 71% [ 9 – 12 ]. Our results were similar to previous findings and emphasized the high mortality rates of these patients. Gram-negative bacterial meningitis has a high mortality rate, and managing this complex disease is challenging [ 13 ]. Besides the inability of antibiotics to cross the blood-brain barrier, the development of multi-drug resistance in microorganisms further aggravates the situation [ 14 ]. A. baumannii is a primary causative agent of gram-negative bacterial meningitis and is often associated with neurosurgical interventions [ 3 , 15 ]. In our study, 48 (92.3%) of 52 meningitis patients affected by A. baumannii had a history of neurosurgery. Our results were similar to those reported in other studies. Reducing the risk of death and increasing the recovery rates for patients suffering from meningitis caused by A. baumannii is urgently required. Therefore, the risk factors affecting mortality need to be determined. However, conducting randomized controlled studies on this subject is difficult. Hence, retrospective studies and the analysis of real-life data are valuable. However, a few studies have investigated the factors affecting the outcome of meningitis caused by A. baumannii . One of these is the study by Guardado et al., which examined the factors affecting treatment outcomes in 51 patients with A. baumannii meningitis. In their study, advanced age and high leukocyte count in the CSF were associated with mortality. In the same study, five patients received intrathecal therapy only, 14 patients received a combination of intrathecal and IV therapy, and the others received IV therapy only. The difference in the mortality of the patients between treatments was not significant [ 16 ]. Sharma et al. conducted a study with 72 patients. They found that being over 40 years old, having a GCS score below 8, having a CSF leucocyte count above 200, the presence of External Ventricular Drain (EVD), and the presence of comorbid diseases were the risk factors affecting mortality [ 17 ]. In 2022, Zheng et al. investigated meningitis caused by non-fermentative Gram-negative bacteria, including A. baumannii, Pseudomonas aeruginosa, and Acinetobacter lwoffii. They reported that hypertension as a comorbid disease, the presence of an external ventricular drain (EVD), and the need for mechanical ventilation were independent risk factors for mortality [ 18 ]. In this study, we examined only patients with meningitis caused by A. baumannii . We evaluated 15 factors by performing multivariate logistic regression analysis. The lack of IVT treatment was identified as an independent risk factor for mortality, increasing the risk of 14-day mortality by 5.6 times and 28-day mortality by 5.3 times. The blood procalcitonin levels before treatment were higher in deceased patients and statistically significant in the univariate analysis. However, in the regression analysis, it was not a significant risk factor for mortality. We did not find a significant difference between deceased and surviving patients regarding other variables examined, including the CSF leucocyte count, patient age, and predisposing disease for meningitis. This was different from the results of other studies. Such differences depend on the characteristics of the established cohort, the patient profile of the hospital where the study was conducted, the physical and medical facilities of the hospital, and other factors. Therefore, national and international multicenter studies on this subject need to be conducted. Our results suggest that both IVT and IV treatments should be administered to patients with meningitis caused by A. baumannii . The administration of IVT/ITH antibiotics makes the CSF sterile and reduces the required time to achieve it [ 18 – 20 ]. Our study showed significantly better microbiological responses in patients who received IVT treatment. It should be noted that the literature does not support the use of IVT/ITH therapy alone, and it is recommended that such therapy be avoided [ 21 ]. In addition, we did not observe any chemical ventriculitis or catheter-related complications in patients receiving IVT treatment. Although we agree with the concerns about chemical meningitis reported in the literature, the absence of such complications in our case series underscores the safety of this treatment. Thus, we emphasize the necessity of adding IVT antibiotics to IV therapy. The Infectious Diseases Society of America's Clinical Practice Guidelines for Healthcare-Associated Ventriculitis and Meningitis (IDSA) recommends using colistimethate sodium or polymyxin B, both IV and IVT/ITH, for treating meningitis caused by carbapenem-resistant strains of Acinetobacter species [ 21 ]. In our study, colistin was administered to 21 patients, and amikacin was administered to five patients as IVT treatment. There was no significant difference in mortality rates between these groups. We suggest using amikacin as an IVT treatment for managing colistin-resistant strains, provided the strains are susceptible to amikacin. In our study, the antibiotic resistance rates were high in the investigated strains. The resistance rates for meropenem-imipenem, amikacin, and colistin were 90.4%, 65.4%, and 12.8%, respectively. Such high resistance rates were likely observed because our data spanned the last five years and included only A. baumannii strains. Antibiotic resistance is continuously increasing, and recent studies have reported similar resistance rates [ 22 , 23 ]. High resistance rates pose significant challenges in selecting microbiologically active treatments [ 24 ]. In our study, 31.9% of patients received inappropriate IV therapy. Although the appropriateness of therapy did not show a statistically significant impact on mortality, the mortality rate was lower in the group that received appropriate treatment. Our findings support a recent meta-analysis that suggests the difficulty of selecting appropriate IV antibiotic therapy in XDR gram-negative bacterial meningitis and highlights the potential mortality-reducing effect of IVT/ITH antibiotic administration. Our study had some limitations. First, it is a retrospective study, and the quality of our filing system limits our results. Secondly, the study did not evaluate some factors that may affect the outcome, such as tumor grading, multiple catheterizations, blood transfusions, etc. Finally, therapeutic drug monitoring is not available in our unit. Therefore, it is not known how many patients have achieved the target drug concentration. However, our study has several strengths. It is one of the largest patient cohorts evaluating meningitis caused by A. baumannii . This comprehensive study examined the patient's demographic characteristics, comorbidities, predisposing factors, laboratory results, and treatment options. Future studies should consider establishing a multicenter prospective cohort to evaluate other risk factors. Conclusion Meningitis caused by Acinetobacter baumannii is a disease with high mortality and is challenging to manage. Selecting the most effective treatment strategy is difficult because the pathogen must be sensitive to the antibiotic, and the selected drug must cross the blood-brain barrier. For patients with meningitis caused by A. baumannii , IVT/ITH treatment is necessary. Our findings showed that adding IVT colistin or amikacin to IV therapy significantly decreases mortality. All centers should be encouraged to share their data regarding this matter, and prospective studies must be conducted to manage the disease. Declarations All of the authors have seen and approved the manuscript. Currently, it has not been sent to any other journal for publication, and it has not been published elsewhere. We confirm that the manuscript complies with all instructions to authors provided by Neurocritical Care . Artificial intelligence (AI)-assisted technology (ChatGPT) was used for language editing and writing refinement during the preparation of this manuscript. However, the study's concept, research design, data analysis, interpretation of results, and discussion were entirely conducted by the authors without any AI assistance. We confirm no plagiarism in this manuscript, including text and images. All authors have reviewed and approved the final content to ensure accuracy, integrity, and originality.This study was approved by the Ethical Committee of Ondokuz Mayis University and by the Administrative Council of the Faculty of Medicine (Grant No.: 2022/426). Funding: The authors declare that no funds, grants, or other support were received during the preparation of this manuscript. Competing Interests : The authors have no relevant financial or non-financial interests to disclose. Ethical Approval : This study was approved by the Ethical Committee of Ondokuz Mayis University and the Administrative Council of the Faculty of Medicine (Grant No.: 2022/426). Sequence Information : Not applicable Author Contributions All authors contributed to the study's conception and design. Fatih Temoçin, Tuba Kuruoglu, Aynur Atilla, Sümeyra Nur Erbaş, and Tuba Sena Karaçeşme performed material preparation, data collection, and analysis. Yeliz Tanriverdi Çaycı did the microbiological analysis. The first draft of the manuscript was written by Fatih Temoçin, Şevki Serhat Baydın, and Esra Tanyel, and all authors commented on previous versions. All authors read and approved the final manuscript. Data availability The datasets generated during and analyzed during the current study are not publicly available but are available from the corresponding author on reasonable request. References Bargiacchi O, Rossati A, Car P, Brustia D, Brondolo R, Rosa F, et al. Intrathecal/intraventricular colistin in external ventricular device-related infections by multi-drug resistant Gram negative bacteria: case reports and review. Infection . 2014;42(5):801-9. doi:10.1007/s15010-014-0618-0 Imberti R, Iotti GA, Regazzi M. Intraventricular or intrathecal colistin for the treatment of central nervous system infections caused by multidrug-resistant Gram-negative bacteria. Expert Rev Anti Infect Ther . 2014;12(4):471-8. doi: 10.1586/14787210.2014.896740 Kourbeti IS, Vakis AF, Ziakas P, Karabetsos D, Potolidis E, Christou S, et al. Infections in patients undergoing craniotomy: risk factors associated with post-craniotomy meningitis. J Neurosurg . 2015;122(5):1113-9. doi: 10.3171/2014.8.JNS132557 Tsimogianni A, Alexandropoulos P, Chantziara V, Vassi A, Micha G, Lagiou F, et al. Intrathecal or intraventricular administration of colistin, vancomycin and amikacin for central nervous system infections in neurosurgical patients in an intensive care unit. Int J Antimicrob Agents . 2017;49(3):389-90. doi:10.1016/j.ijantimicag.2017.01.002 Ye Y, Kong Y, Ma J, Shi G. Carbapenem-Resistant Gram-Negative Bacteria-Related Healthcare-Associated Ventriculitis and Meningitis: Antimicrobial Resistance of the Pathogens, Treatment, and Outcome. Microbiol Spectr . 2022;10(3):e0025322. doi:10.1128/spectrum.00253-22 Jain R, Danziger LH. Multidrug-resistant Acinetobacter infections: an emerging challenge to clinicians. Ann Pharmacother . 2004;38(9):1449-59. doi:10.1345/aph.1D592 Benifla M, Zucker G, Cohen A, Alkan M. Successful treatment of Acinetobacter meningitis with intrathecal polymyxin E. J Antimicrob Chemother . 2004;54(1):290-2. doi: 10.1093/jac/dkh289. Horan TC, Andrus M, Dudeck MA. CDC/NHSN surveillance definition of health care-associated infection and criteria for specific types of infections in the acute care setting. Am J Infect Control . 2008;36(5):309-32. doi:10.1016/j.ajic.2008.03.002 Ni S, Li S, Yang N, Zhang S, Hu D, Li Q, et al. Post-neurosurgical meningitis caused by Acinetobacter baumannii : case series and review of the literature. Int J Clin Exp Med . 2015;8(11):21833-8. Gao JG, Ye Y. Clinical manifestations and risk factors of poor prognosis of Acinetobacter baumannii intracranial infection. Zhonghua Yi Xue Za Zhi . 2018;98(37):2973-7. doi:10.3760/cma.j.issn.0376-2491.2018.37.004 Metan G, Alp E, Aygen B, Sumerkan B. Acinetobacter baumannii meningitis in post-neurosurgical patients: clinical outcome and impact of carbapenem resistance. J Antimicrob Chemother . 2007;60(1):197-9. doi: 10.1093/jac/dkm181 Huttova M, Freybergh PF, Rudinsky B, Sramka M, Kisac P, Bauer F, et al. Postsurgical meningitis caused by Acinetobacter baumannii associated with high mortality. Neuro Endocrinol Lett . 2007;28 Suppl 2:15-6. van de Beek D, Drake JM, Tunkel AR. Nosocomial bacterial meningitis. N Engl J Med . 2010;362(2):146-54. doi:10.1056/NEJMra0804573 Falagas ME, Bliziotis IA, Tam VH. Intraventricular or intrathecal use of polymyxins in patients with Gram-negative meningitis: a systematic review of the available evidence. Int J Antimicrob Agents . 2007;29(1):9-25. doi:10.1016/j.ijantimicag.2006.08.024 Kim BN, Peleg AY, Lodise TP, Lipman J, Li J, Nation R, et al. Management of meningitis due to antibiotic-resistant Acinetobacter species. Lancet Infect Dis . 2009;9(4):245-55. doi:10.1016/s1473-3099(09)70055-6 Rodríguez Guardado A, Blanco A, Asensi V, Pérez F, Rial JC, Pintado V, et al. Multidrug-resistant Acinetobacter meningitis in neurosurgical patients with intraventricular catheters: assessment of different treatments. J Antimicrob Chemother . 2008;61(4):908-13. doi:10.1093/jac/dkn018 Sharma R, Goda R, Borkar SA, Katiyar V, Agarwal S, Kumar A, et al. Outcome following postneurosurgical Acinetobacter meningitis: an institutional experience of 72 cases. Neurosurg Focus . 2019;47(2):E8. doi:10.3171/2019.5.Focus19278 Zheng G, Wang S, Lv H, Zhang G. Nomogram Analysis of Clinical Characteristics and Mortality Risk Factor of Non-Fermentative Gram-Negative Bacteria-Induced Post-Neurosurgical Meningitis. Infect Drug Resist . 2022;15:6379-6389. doi: 10.2147/IDR.S385502. Remeš F, Tomáš R, Jindrák V, Vaniš V, Setlík M. Intraventricular and lumbar intrathecal administration of antibiotics in postneurosurgical patients with meningitis and/or ventriculitis in a serious clinical state. J Neurosurg . 2013;119(6):1596-602. doi:10.3171/2013.6.Jns122126 Khan SA, Waqas M, Siddiqui UT, Shamim MS, Nathani KR, Jooma R, et al. Intrathecal and intraventricular antibiotics for postoperative Gram-negative meningitis and ventriculitis. Surg Neurol Int . 2017;8:226. doi:10.4103/sni.sni_81_17 Tunkel AR, Hasbun R, Bhimraj A, Byers K, Kaplan SL, Scheld WM, et al. 2017 Infectious Diseases Society of America's Clinical Practice Guidelines for Healthcare-Associated Ventriculitis and Meningitis. Clin Infect Dis . 2017;64(6):e34-e65. doi:10.1093/cid/ciw861 Ahsan U, Mushtaq F, Saleem S, Malik A, Sarfaraz H, Shahzad M, et al. Emergence of high colistin resistance in carbapenem resistant Acinetobacter baumannii in Pakistan and its potential management through immunomodulatory effect of an extract from Saussurea lappa. Front Pharmacol . 2022;13:986802. doi:10.3389/fphar.2022.986802 Cafiso V, Stracquadanio S, Dovere V, Lo Verde F, Zega A, Pigola G, et al. Colistin Resistance Onset Strategies and Genomic Mosaicism in Clinical Acinetobacter baumannii Lineages. Pathogens . 2021;10(11). doi: 10.3390/pathogens10111516 Li MT, Wu QQ, Li JB, Chen JS. Intrathecal or intraventricular antimicrobial therapy for post-neurosurgical Gram-negative bacillary meningitis or ventriculitis: a systematic review and meta-analysis. Int J Antimicrob Agents . 2024 Jan;63(1):107033. doi: 10.1016/j.ijantimicag.2023.107033. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6165448","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":432295132,"identity":"bff2ef35-0b49-4979-9dec-b71925c4a3df","order_by":0,"name":"Fatih Temoçin","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA60lEQVRIiWNgGAWjYBAC9gYGhsMwzgGGCghDAp8WngPMIC0GUC1n4FoM8GphhitgbCNGC/v5g4cLGP7I6bY3PzxcOM8m2uAA88HbPAx/8nFq4UlmODyDwcDY7Mwxg8Mzt6XlbjjAlmzNw2Bg2YBDiz0DUAtQQeK2GzkMh3m3HQZq4TGTBorgdBkP/2OwlnqIljkgLfzf8GuRgNiSYAbW0gC2hY2AlscGh3kMjA23gfzCcywtd+ZhNmPLOQbGeByW+PgzT4WcvNnxZiCjxia373jzwxtvKuRwhzIYoEgzY4iMglEwCkbBKCAVAAB9t1Ex6PXUlQAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0000-0002-4819-8242","institution":"Ondokuz Mayis University Faculty of Medicine: Ondokuz Mayis Universitesi Tip Fakultesi","correspondingAuthor":true,"prefix":"","firstName":"Fatih","middleName":"","lastName":"Temoçin","suffix":""},{"id":432295133,"identity":"7f15a696-f781-41a6-878c-616e7a1289cc","order_by":1,"name":"Tuba Kuruoglu","email":"","orcid":"","institution":"Ondokuz Mayis University Faculty of Medicine: Ondokuz Mayis Universitesi Tip Fakultesi","correspondingAuthor":false,"prefix":"","firstName":"Tuba","middleName":"","lastName":"Kuruoglu","suffix":""},{"id":432295134,"identity":"62a31727-4b48-4293-8b51-c716c7ec42a0","order_by":2,"name":"Sümeyra Nur Erbaş","email":"","orcid":"","institution":"Ondokuz Mayis University Faculty of Medicine: Ondokuz Mayis Universitesi Tip Fakultesi","correspondingAuthor":false,"prefix":"","firstName":"Sümeyra","middleName":"Nur","lastName":"Erbaş","suffix":""},{"id":432295135,"identity":"4832dd61-ba76-4c5c-8644-288b4dd8c512","order_by":3,"name":"Tuba Sena Karaçeşme","email":"","orcid":"","institution":"Ondokuz Mayis University Faculty of Medicine: Ondokuz Mayis Universitesi Tip Fakultesi","correspondingAuthor":false,"prefix":"","firstName":"Tuba","middleName":"Sena","lastName":"Karaçeşme","suffix":""},{"id":432295136,"identity":"4b255c07-eea3-40aa-9461-04697099e936","order_by":4,"name":"Aynur Atilla","email":"","orcid":"","institution":"Ondokuz Mayis University Faculty of Medicine: Ondokuz Mayis Universitesi Tip Fakultesi","correspondingAuthor":false,"prefix":"","firstName":"Aynur","middleName":"","lastName":"Atilla","suffix":""},{"id":432295137,"identity":"d5a1ba06-525a-47f5-b323-0ef96d2bb442","order_by":5,"name":"Şevki Serhat Baydın","email":"","orcid":"","institution":"Ondokuz Mayis University Faculty of Medicine: Ondokuz Mayis Universitesi Tip Fakultesi","correspondingAuthor":false,"prefix":"","firstName":"Şevki","middleName":"Serhat","lastName":"Baydın","suffix":""},{"id":432295138,"identity":"4dc76f7b-b187-4aeb-a6dd-2561f4ebfc66","order_by":6,"name":"Yeliz Tanriverdi Çaycı","email":"","orcid":"","institution":"Ondokuz Mayis University Faculty of Medicine: Ondokuz Mayis Universitesi Tip Fakultesi","correspondingAuthor":false,"prefix":"","firstName":"Yeliz","middleName":"Tanriverdi","lastName":"Çaycı","suffix":""},{"id":432295139,"identity":"7c373ef2-fc20-4db3-aace-83b319010fa4","order_by":7,"name":"Esra Tanyel","email":"","orcid":"","institution":"Ondokuz Mayis University Faculty of Medicine: Ondokuz Mayis Universitesi Tip Fakultesi","correspondingAuthor":false,"prefix":"","firstName":"Esra","middleName":"","lastName":"Tanyel","suffix":""}],"badges":[],"createdAt":"2025-03-05 20:52:17","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6165448/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6165448/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":81838184,"identity":"b2d6a3e7-d978-4ff6-b249-3d54f962e1b0","added_by":"auto","created_at":"2025-05-02 15:26:03","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1155901,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6165448/v1/a44251b6-c973-408b-9edd-5b8a0964fe5e.pdf"}],"financialInterests":"","formattedTitle":"Meningitis Caused by Extensively Drug-Resistant Acinetobacter baumannii: Treatment Options and Factors Affecting Outcomes","fulltext":[{"header":"Introduction","content":"\u003cp\u003eOne of the most important complications after neurosurgery operations is central nervous system (CNS) infections. Gram-positive cocci are the most common pathogens, while gram-negative bacteria cause approximately 15% of CNS infections [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. \u003cem\u003eAcinetobacter baumannii\u003c/em\u003e (\u003cem\u003eA. baumannii\u003c/em\u003e) is the most common pathogen of healthcare-associated gram-negative bacterial meningitis [\u003cspan additionalcitationids=\"CR4\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. In the absence of appropriate treatment, the mortality rate of affected patients can be pretty high (15\u0026ndash;70%). An increased infection rate caused by the strains of MDR-\u003cem\u003eA. baumannii\u003c/em\u003e has recently been reported [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Treating infections caused by multi-drug-resistant (MDR) and extensively drug-resistant (XDR) strains of bacteria has become extremely difficult. Although multidrug-resistant strains of \u003cem\u003eA. baumannii\u003c/em\u003e are a global concern, studies on nosocomial meningitis cases caused by \u003cem\u003eA. baumannii\u003c/em\u003e are limited.\u003c/p\u003e \u003cp\u003eThe options for treating patients with meningitis caused by \u003cem\u003eA. baumannii\u003c/em\u003e are extremely limited because the choice of antibiotic depends not only on the sensitivity of the pathogen to the antibiotic but also on the penetration of the selected antibiotic through the blood-brain barrier. Therefore, to treat meningitis caused by A. baumannii, intrathecal (ITH) or intraventricular (IVT) antibiotics should be administered along with intravenous antibiotics.\u003c/p\u003e \u003cp\u003eIn this study, we analyzed the clinical features of nosocomial meningitis caused by \u003cem\u003eA. baumannii\u003c/em\u003e to identify the factors affecting the outcome, compare the effectiveness of different therapeutic regimens, and determine the antimicrobial resistance rates of the pathogen.\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cp\u003e We conducted a single-center retrospective study in a large regional hospital affiliated with Ondokuz Mayis University, Faculty of Medicine, Infectious Diseases, and Neurosurgery clinics. Our hospital is located in the Black Sea region of Turkey and has 110 third-level intensive care beds, with a total bed capacity of 1,100. The study included meningitis patients caused by \u003cem\u003eA.baumannii\u003c/em\u003e for 2017\u0026ndash;2022. The data were collected from archives of infectious diseases, the neurosurgery clinic, and the digital archives of the hospital. Meningitis diagnosis criteria were defined according to the Centers for Disease Control and Prevention (CDC) [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e \u003cem\u003eInclusion criteria;\u003c/em\u003e \u003c/p\u003e \u003cp\u003e \u003col\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003ePatients with at least 2 of the following signs or symptoms with no other recognized cause: headache, dizziness, fever (\u0026gt;\u0026thinsp;38\u0026deg;C), localizing neurologic signs, changing level of consciousness, or confusion\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003e\u003cem\u003eA. baumannii\u003c/em\u003e growth in cerebrospinal fluid (CSF) culture\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eIncreased white cells, elevated protein, and/or decreased glucose in CSF\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003c/ol\u003e \u003c/p\u003e \u003cp\u003eThe following patients were excluded from the study:\u003c/p\u003e \u003cp\u003e \u003col\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003ePatients under 18 years of age\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003ePatients with polymicrobial growth in the CSF culture\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003ePatients receiving treatment for less than 48 h\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003ePatients with hematological malignancies\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eIsolations of \u003cem\u003eAcinetobacter\u003c/em\u003e species other than \u003cem\u003eA. baumannii\u003c/em\u003e\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003ePatients with another concomitant nosocomial infection\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003ePatients for whom demographic data, medical history, and treatment data were missing\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003c/ol\u003e \u003c/p\u003e \u003cp\u003e This study was approved by the Ethical Committee of Ondokuz Mayis University and the Administrative Council of the Faculty of Medicine (Grant No.: 2022/426).\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eEpidemiological data\u003c/h2\u003e \u003cp\u003eBesides recording the data on the demographic characteristics of the patients, we also recorded the underlying diseases, whether the patient underwent cranial surgery, the number of cranial surgeries, time to diagnosis of meningitis after surgery, number of days hospitalized before diagnosis, prior use of antibiotics, the results of the \u003cem\u003ecerebrospinal fluid\u003c/em\u003e (CSF) microbiological and biochemical analysis at diagnosis, blood culture at diagnosis, white blood cell count, CRP and procalcitonin values, fever at the time of diagnosis, hypotension, and Glasgow coma scale (GCS) score, treatments administered for meningitis and, treatment responses. Prior use of antibiotics was defined as a treatment for at least 48 h during the 10 days before the diagnosis of meningitis.\u003c/p\u003e \u003cp\u003eThe antibiotic resistance profile of the pathogenic microorganism was also recorded and analyzed.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eMicrobiological analysis\u003c/h3\u003e\n\u003cp\u003eAll CSF samples were analyzed in our center's microbiology laboratory. The antimicrobial susceptibilty of the isolates was determined by VITEK\u0026reg; 2 Compakt (bioM\u0026eacute;rieux, Inc., Marcy l'Etoile, France) automated system. \u003cem\u003eAcinetobacter baumannii\u003c/em\u003e was identified by the automated Matrix-Assisted Laser Desorption Ionization-Time of Flight (MALDI-TOF) Mass Spectrometry system (Vitek MS\u0026reg; systems, bioM\u0026eacute;rieux, Inc., Marcy l'Etoile, France). The in-vitro antibiotic susceptibility of the isolates was determined based on the European Committee on Antimicrobial Susceptibility Testing (EUCAST) criteria. Colistin susceptibility testing was performed using 96-well broth microdilution (BMD) panels following EUCAST recommendations. According to EUCAST criteria, isolates with a colistin minimum inhibitory concentration (MIC) of \u0026gt;\u0026thinsp;2 \u0026micro;g/mL were considered resistant.\u003c/p\u003e\n\u003ch3\u003eTreatment and cure\u003c/h3\u003e\n\u003cp\u003eThe treatment choice and route of administration are at the treating clinician's discretion. No other protocol was used for the study. Following the initial diagnosis of meningitis, treatment consisted of the following parenterally administered antibiotics, used either as monotherapy or in combination therapy: meropenem 2 g/8 h as a 3-hour extended infusion, amikacin 500 mg/12 h, ampicillin/sulbactam 3 g/8 h, tigecycline (100 mg IV initially, followed by 50 mg/12 h), and colistin sulfomethate sodium 5 mg/kg/day in three divided doses. Antibiotic doses were adjusted according to the patient's renal function. Intraventricular treatments included colistin (polymyxin E) methanesulfonate (12,500 IU\u0026thinsp;=\u0026thinsp;1 mg) 10 mg/day, or amikacin 30 mg/day.\u003c/p\u003e \u003cp\u003eIntravenous antibiotics were classified as appropriate or inappropriate based on the microbiological activity against \u003cem\u003eA. baumannii\u003c/em\u003e. If the IV regimen included at least one microbiologically active agent, it was classified as an appropriate treatment. Conversely, the treatment was classified as inappropriate if none of the administered IV antibiotics were active against the pathogen.\u003c/p\u003e \u003cp\u003ePatients were followed until hospital death or discharge. Treatment response was assessed by 14-day and 28-day mortality. The microbiological cure was accepted as no growth in CSF control cultures performed after at least 48 hours of treatment.\u003c/p\u003e\n\u003ch3\u003eUse of Artificial Intelligence\u003c/h3\u003e\n\u003cp\u003eDuring the preparation of this manuscript, artificial intelligence (AI)-assisted technology (ChatGPT-Model o1) was used solely for language editing and writing improvement.\u003c/p\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eThe data were analyzed using IBM SPSS V23. The Kolmogorov-Smirnov and Shapiro-Wilk tests were conducted to determine whether the data followed a normal distribution. Binary logistic regression analysis was performed to examine the mortality risk factors on days 14 and 28. The enter method was used to include the independent variables in the model. The results of the analyses were presented as frequency (percentage) for categorical variables and mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation for quantitative variables. All differences were considered to be statistically significant at p\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eWe analyzed data of those patients (n\u0026thinsp;=\u0026thinsp;52) who met the inclusion criteria. Among the participants, 24 were male, and 28 were female; their mean age was 54.5\u0026thinsp;\u0026plusmn;\u0026thinsp;16.9 years. We found that 33 patients (63.5%) were hospitalized in the intensive care unit, and 19 (36.5%) were hospitalized in the neurosurgery and infectious diseases service. The mean number of days of hospitalization was 22.9\u0026thinsp;\u0026plusmn;\u0026thinsp;15.2. Also, 48 patients had various neurosurgical interventions, and four had no neurosurgery or procedure. The most common neurosurgical diagnosis was spontaneous intracranial hemorrhage.\u003c/p\u003e \u003cp\u003eMoreover, 50% of the patients had a history of external ventricular drainage, and 28.8% had a history of craniotomy. Comorbid conditions were present in 67.3% of the patients. The most common comorbid condition was hypertension, affecting 48.1% of the patients. \u003cem\u003eA. baumannii\u003c/em\u003e was also detected in the blood cultures of 17.3% of the patients. The 14-day mortality rate was 26.9%, and the 28-day mortality rate was 42.3%. The demographic data and the clinical and laboratory characteristics of the participants are presented in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eDemographic data and the clinical and laboratory characteristics\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNo. of patients n.52\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003ePercentage %\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGender(M/F)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e24/28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e46.2/53.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;Std. deviation)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e54.5\u0026thinsp;\u0026plusmn;\u0026thinsp;16.9\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFever at diagnosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e55.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHypotension at diagnosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e26.9\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCharlson Comorbidity Index [median (min-max)]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e3 (0\u0026ndash;11)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eComorbidities\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e67.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDiabetes mellitus\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e23.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHypertension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e48.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePulmonary diseases\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e3.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003eInpatient clinic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIntensive care unit*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e63.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWards\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e36.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDay of hospitalization (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;Std.Deviation)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e22.9\u0026thinsp;\u0026plusmn;\u0026thinsp;15.2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003ePrimary neurosurgical diagnose\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSpontaneous intracranial hemorrhage\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e67.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTraumatic head injury\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e11.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBrain tumor\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e7.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHydrocephalus\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e3.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo neurosurgical diagnose\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e9.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003eNeurosurgical history\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCraniotomy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e28.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eExternal ventricular drainage\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e50\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVentriculoperitoneal shunt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e7.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCerebral embolisation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e5.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo neurosurgical history\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e7.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNumber of neurosurgery [median (min-max)]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e2 (0\u0026ndash;8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003eLaboratory findings [mean\u0026thinsp;\u0026plusmn;\u0026thinsp;Std.Deviation (min-max)]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBlood WBC (count/uL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e13802.5\u0026thinsp;\u0026plusmn;\u0026thinsp;6863.1 (2990\u0026ndash;36060)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBlood CRP (mg/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e125.1\u0026thinsp;\u0026plusmn;\u0026thinsp;112 (2-385)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBlood Procalcitonin (ng/mL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e8.2\u0026thinsp;\u0026plusmn;\u0026thinsp;10.8 (0.2\u0026ndash;86.3)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCerebrospinal fluid leukocyte (count/mm\u003csup\u003e3\u003c/sup\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e855\u0026thinsp;\u0026plusmn;\u0026thinsp;104 (0-10000)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCerebrospinal fluid glucose (mg/dL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e55.1\u0026thinsp;\u0026plusmn;\u0026thinsp;43 (1-143)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCerebrospinal fluid protein (mg/dL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e253\u0026thinsp;\u0026plusmn;\u0026thinsp;310 (6-1138)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePositive blood culture for \u003cem\u003eA. baumannii\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e17.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003eClinical outcome\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e14-day mortality\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e26.9\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e28-day mortality\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e42.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMicrobiologic cure\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e57.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003e* ICU admission for at least 48 hours during the entire hospital stay.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eA total of 26 patients (50%) received only intravenous (IV) antibiotics, while the remaining 26 patients (50%) received both IV and intraventricular (IVT) antibiotics. Among those who received only IV therapy, the most commonly used regimen was meropenem plus colistin (17 patients, 65.3%), followed by meropenem monotherapy. In the IVT group, colistin was administered to 21 patients, and amikacin to 5. The most frequently used combination in the IVT group was IV meropenem\u0026thinsp;+\u0026thinsp;IV colistin\u0026thinsp;+\u0026thinsp;IVT colistin (14 patients). Detailed information on all administered treatments is provided in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAntibiotics used for the treatment of meningitis\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTreatment\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNo. of patients n.52\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePersentage %\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOnly IV treatment\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e50\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMeropenem\u0026thinsp;+\u0026thinsp;Colistin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e65.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMeropenem\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e26.9\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMeropenem\u0026thinsp;+\u0026thinsp;Amikacin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMeropenem\u0026thinsp;+\u0026thinsp;Sulbactam ampicilin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIV plus Intraventricular treatment*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e50\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMeropenem\u0026thinsp;+\u0026thinsp;Colistin\u0026thinsp;+\u0026thinsp;Intraventricular Colistin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e53.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMeropenem\u0026thinsp;+\u0026thinsp;Colistin\u0026thinsp;+\u0026thinsp;Intraventricular Amikacin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMeropenem\u0026thinsp;+\u0026thinsp;Intraventricular Colistin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMeropenem\u0026thinsp;+\u0026thinsp;Intraventricular Amikacin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMeropenem\u0026thinsp;+\u0026thinsp;Amikacin\u0026thinsp;+\u0026thinsp;Intraventricular Amikacin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMeropenem\u0026thinsp;+\u0026thinsp;Amikacin\u0026thinsp;+\u0026thinsp;Intraventricular Colistin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMeropenem\u0026thinsp;+\u0026thinsp;Tigecycline\u0026thinsp;+\u0026thinsp;Intraventricular Amikacin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eColistin\u0026thinsp;+\u0026thinsp;Intraventricular Colistin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"3\"\u003e*Amikacin 30 mg/day and colistin (polymyxin E) methanesulfonate (12.500 IU\u0026thinsp;=\u0026thinsp;1 mg) 10 mg/day were administered\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe univariate analysis of the factors affecting mortality showed that the 14-day mortality risk was 5.6 times, the 28-day mortality risk was 5.3 times higher for the patients who did not receive IVT treatment [p\u0026thinsp;=\u0026thinsp;0.018, OR: 5.622 (1.342\u0026ndash;23.559); p\u0026thinsp;=\u0026thinsp;0.007, OR: 5.333 (1.595\u0026ndash;17.829), respectively]. The higher risk of 14-day and 28-day mortality in those patients who did not receive IVT therapy was also confirmed by the results of the multivariate analysis [p\u0026thinsp;=\u0026thinsp;0.032, OR: 15.341; p\u0026thinsp;=\u0026thinsp;0.039, OR: 9.273, respectively]. While 10 of 26 patients (38.4%) who received only IV treatment achieved microbiological cure, 20 of 26 patients (76.9%) who received IV\u0026thinsp;+\u0026thinsp;IVT treatment achieved microbiological cure, and the difference was statistically significant (p\u0026thinsp;=\u0026thinsp;0.005).\u003c/p\u003e \u003cp\u003eFor the 26 patients who received IVT therapy, the difference in their 14-day and 28-day mortality rates after colistin or amikacin was insignificant (p\u0026thinsp;=\u0026thinsp;0.51, p\u0026thinsp;=\u0026thinsp;0.63, respectively). Additionally, no chemical ventriculitis or catheter-related complications were detected in IVT treatment patients.\u003c/p\u003e \u003cp\u003eIn the univariate analysis, the blood procalcitonin values before treatment were significantly higher in the deceased patients [p\u0026thinsp;=\u0026thinsp;0.03, OR: 1.026 (0.992\u0026ndash;1.062)], but in the multivariate analysis, they were not significant.\u003c/p\u003e \u003cp\u003eThe age, gender, underlying chronic diseases, Charlson Comorbidity Index, pre-diagnostic antibiotic use, and the results of the CSF cytological and biochemical analysis of the mortality of the patients did not have a significant effect. The examined risk factors affecting the 14-day and 28-day mortality are shown in Tables\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e and \u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e. Our analysis included the diagnoses of spontaneous intracranial hemorrhage, head trauma, brain tumor, and hydrocephalus, which are thought to predispose patients to develop meningitis. However, no statistically significant associations were found between these diagnoses and 14- or 28-day mortality (p\u0026thinsp;=\u0026thinsp;0.27, p\u0026thinsp;=\u0026thinsp;0.84, respectively).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAnalysis of the risk factors affecting the 14-day mortality, determined by binary logistic regression analysis\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eCharacteristics\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eOutcome\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003eUnivariate\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eMultivariate analysis\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSurvived(n\u0026thinsp;=\u0026thinsp;38)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eDead(n\u0026thinsp;=\u0026thinsp;14)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eOR (%95 CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eOR (%95 CI)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGender (Female/Male)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e20/18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8/6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.77\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.833 (0.242\u0026ndash;2.866)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.447\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.442 (0.054\u0026ndash;3.627)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;Std.Deviation)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e53.61\u0026thinsp;\u0026plusmn;\u0026thinsp;16.21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e57\u0026thinsp;\u0026plusmn;\u0026thinsp;19.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.52\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.012 (0.975\u0026ndash;1.051)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.548\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0..923 (0.892\u0026ndash;1.130)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFever at diagnosis (Yes/No)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e20/18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9/5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.620 (0.457\u0026ndash;5.741)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.755\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.715 (0.088\u0026ndash;5.848)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHypotension at diagnosis (Yes/No)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10/28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4/10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.120 (0.286\u0026ndash;4.390)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.465\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.462 (0.058\u0026ndash;3.660)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGlaskow Coma Scale [Median (min-max)]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8(3\u0026ndash;15)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10(3\u0026ndash;15)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.107 (0.942\u0026ndash;1.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.332\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.178 (0.846\u0026ndash;1.640)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCharlson Comorbidity Index [Median (min-max)]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 (0\u0026ndash;9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (0\u0026ndash;11)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.490\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.093 (0.849\u0026ndash;1.406)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.643\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.105 (0.725\u0026ndash;1.682)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFrequency of neurosurgery\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2(0\u0026ndash;8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1(0\u0026ndash;8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.039 (0.733\u0026ndash;1.474)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.151\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.423 (0.879\u0026ndash;2.306)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStay before the diagnosis (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;Std.Deviation)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11.29\u0026thinsp;\u0026plusmn;\u0026thinsp;10.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.25\u0026thinsp;\u0026plusmn;\u0026thinsp;9.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.642\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.99 (0.949\u0026ndash;1.033)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eICU/Clinic ward\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e24/14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9/5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.952 (0.266\u0026ndash;3.414)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.192\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.116 (0.005\u0026ndash;2.936)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChronic Diseases (Yes/No)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e27/11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8/6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.841 (0.517\u0026ndash;6.553)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.213\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.139 (0.138\u0026ndash;4.347)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDiabetes Mellitus\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8/30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4/9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.6 (0.146\u0026ndash;2.464)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHypertension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e19/19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6/8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.333 (0.388\u0026ndash;4.584)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePrior use of antibiotics (Yes/No)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e23/15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6/8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2.044 (0.59\u0026ndash;7.082)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.525\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.872 (0.271\u0026ndash;12.951)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"7\" nameend=\"c7\" namest=\"c1\"\u003e \u003cp\u003eLaboratory findings at the time of diagnosis (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;Std.Deviation)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCerebrospinal fluid leukocyte (count/mm3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e427.89\u0026thinsp;\u0026plusmn;\u0026thinsp;660.62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2014.29\u0026thinsp;\u0026plusmn;\u0026thinsp;3623.26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.078\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1 (1\u0026ndash;1.001)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCerebrospinal fluid glucose (mg/dL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e54.21\u0026thinsp;\u0026plusmn;\u0026thinsp;40.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e57.69\u0026thinsp;\u0026plusmn;\u0026thinsp;51.69\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.002 (0.987\u0026ndash;1.017)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.351\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.823 (0.753\u0026ndash;1.108)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCerebrospinal fluid protein (mg/dL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e165.35\u0026thinsp;\u0026plusmn;\u0026thinsp;249.83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e205.77\u0026thinsp;\u0026plusmn;\u0026thinsp;345.78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.435\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1 (0.998\u0026ndash;1.003)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.686\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.001 (0.998\u0026ndash;1.004)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBlood CRP (mg/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e118\u0026thinsp;\u0026plusmn;\u0026thinsp;109.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e154.84\u0026thinsp;\u0026plusmn;\u0026thinsp;118.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.003 (0.997\u0026ndash;1.008)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBlood Procalcitonin (ng/mL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e4.73\u0026thinsp;\u0026plusmn;\u0026thinsp;17.01\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e16.83\u0026thinsp;\u0026plusmn;\u0026thinsp;27.29\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.03\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e1.026 (0.992\u0026ndash;1.062)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBlood WBC (count/uL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e13824.61\u0026thinsp;\u0026plusmn;\u0026thinsp;6980.78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13740.71\u0026thinsp;\u0026plusmn;\u0026thinsp;6788.74\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1 (1\u0026ndash;1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.385\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1 (1\u0026ndash;1)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIntraventricular treatment (Yes/No)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e23/15\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e3/11\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.02\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e5.622 (1.342\u0026ndash;23.559)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.032\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e15.341 (1.260\u0026ndash;186.832)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAppropriateness of treatment (Appropriate/Inappropriate)*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e24/11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8/4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.903\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.091 (0.270\u0026ndash;4.408)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.098\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e8.746(0.671-113.924)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"7\"\u003eCox \u0026amp; Snell R\u003csup\u003e2\u003c/sup\u003e= %25.1; Nagelkerke R\u003csup\u003e2\u003c/sup\u003e= %37.2\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"7\"\u003e* Five patients were excluded from the analysis due to a lack of data on colistin susceptibility.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAnalysis of risk factors affecting the 28-day mortality, determined by binary logistic regression analysis\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eCharacteristics\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eOutcome\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003eUnivariate\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eMultivariate analysis\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSurvived(n\u0026thinsp;=\u0026thinsp;30)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eDead(n\u0026thinsp;=\u0026thinsp;22)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eOR (%95 CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eOR (%95 CI)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGender (Female/Male)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e17/13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11/11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.634\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.308 (0.433\u0026ndash;3.946)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.159\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.241 (0.033\u0026ndash;1.744)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;Std.Deviation)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e54.57\u0026thinsp;\u0026plusmn;\u0026thinsp;16.54\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e54.45\u0026thinsp;\u0026plusmn;\u0026thinsp;17.77\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.981\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1 (0.967\u0026ndash;1.033)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.932\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.943 (0.901\u0026ndash;1.086)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFever at diagnosis (Yes/No)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15/15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e14/8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.750 (0.568\u0026ndash;5.393)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.935\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.924 (0.140\u0026ndash;6.111)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHypotension at diagnosis (Yes/No)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6/24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8/14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.194\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2.286 (0.657\u0026ndash;7.954)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.130\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.229 (0.034\u0026ndash;1.541)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGlaskow Coma Scale [Median (min-max)]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8(3\u0026ndash;15)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10(3\u0026ndash;15)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.128\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.122 (0.967\u0026ndash;1.302)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.265\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.184 (0.880\u0026ndash;1.593)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCharlson Comorbidity Index [Median (min-max)]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 (0\u0026ndash;9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (1\u0026ndash;11)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.670\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.001 (0.625\u0026ndash;1.049)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.616\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.095 (0.768\u0026ndash;1.560)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFrequency of neurosurgery\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2(0\u0026ndash;8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1(0\u0026ndash;8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.395\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.86 (0.608\u0026ndash;1.217)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.835\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.049 (0.670\u0026ndash;1.641)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStay before the diagnosis (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;Std.Deviation)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e25.87\u0026thinsp;\u0026plusmn;\u0026thinsp;15.23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e19\u0026thinsp;\u0026plusmn;\u0026thinsp;14.61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.114\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.968 (0.929\u0026ndash;1.008)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eICU/Clinic ward\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e19/11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e14/8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.982\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.987 (0.315\u0026ndash;3.095)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.225\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.195 (0.012\u0026ndash;3.248)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChronic Diseases (Yes/No)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e20/10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e15/7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.908\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.933 (0.288\u0026ndash;3.023)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.298\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.041 (0.003\u0026ndash;2.746)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDiabetes Mellitus\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5/25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8/14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.174\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.4 (0.107\u0026ndash;1.499)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHypertension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12/18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13/9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.176\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.462 (0.15\u0026ndash;1.415)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePrior use of antibiotics (Yes/No)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18/12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11/11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.474\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.5 (0.494\u0026ndash;4.551)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.609\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.625 (0.103\u0026ndash;3.784)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"7\" nameend=\"c7\" namest=\"c1\"\u003e \u003cp\u003eLaboratory findings at the time of diagnosis (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;Std.Deviation)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCerebrospinal fluid leukocyte (count/mm3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e467.33\u0026thinsp;\u0026plusmn;\u0026thinsp;703.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1383.64\u0026thinsp;\u0026plusmn;\u0026thinsp;2988.52\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.175\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1 (1\u0026ndash;1.001)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCerebrospinal fluid glucose (mg/dL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e51.23\u0026thinsp;\u0026plusmn;\u0026thinsp;36.22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e60.05\u0026thinsp;\u0026plusmn;\u0026thinsp;50.74\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.482\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.005 (0.991\u0026ndash;1.019)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.280\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.001 (0.971\u0026ndash;1.047)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCerebrospinal fluid protein (mg/dL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e132.20\u0026thinsp;\u0026plusmn;\u0026thinsp;193.24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e232.70\u0026thinsp;\u0026plusmn;\u0026thinsp;351.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.316\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.001 (0.999\u0026ndash;1.003)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.181\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.002 (0.999\u0026ndash;1.006)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBlood CRP (mg/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e122.95\u0026thinsp;\u0026plusmn;\u0026thinsp;113.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e134.93\u0026thinsp;\u0026plusmn;\u0026thinsp;112.21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.703\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.001 (0.996\u0026ndash;1.006)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBlood Procalcitonin (ng/mL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e5.79\u0026thinsp;\u0026plusmn;\u0026thinsp;19.23\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e11.24\u0026thinsp;\u0026plusmn;\u0026thinsp;22.96\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.043\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e2.013 (0.981\u0026ndash;2.047)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBlood WBC (count/uL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14099.77\u0026thinsp;\u0026plusmn;\u0026thinsp;7838.62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13396\u0026thinsp;\u0026plusmn;\u0026thinsp;5407.68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.713\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1 (1\u0026ndash;1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.534\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1 (1\u0026ndash;1)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIntraventricular treatment (Yes/No)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e20/10\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e6/16\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.007\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e5.333 (1.595\u0026ndash;17.829)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.039\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e9.273 (1.124\u0026ndash;76.485)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAppropriateness of treatment (Appropriate/Inappropriate)*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18/9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e14/6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.965\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.221 (0.733\u0026ndash;3.25)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.234\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.541 (0.441\u0026ndash;28.469)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"7\"\u003eCox \u0026amp; Snell R\u003csup\u003e2\u003c/sup\u003e= %31.2; Nagelkerke R\u003csup\u003e2\u003c/sup\u003e= %41.7\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"7\"\u003e*Five patients were excluded from the analysis due to a lack of data on colistin susceptibility.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe meropenem resistance rate was 90.4%, and the colistin resistance rate was 12.8% for the 52 \u003cem\u003eA. baumannii\u003c/em\u003e strains that were included in the study. The antibiotic resistance rates of the pathogen are presented in Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e. Evaluation of the microbiological activity of the intravenous treatments revealed that 32 patients received appropriate therapy, while 15 received inappropriate therapy. In five patients treated with colistin, the appropriateness of therapy could not be assessed due to the lack of data regarding the colistin susceptibility of \u003cem\u003eA. baumannii\u003c/em\u003e. Although mortality was lower in the group that received appropriate therapy, no statistically significant differences were observed in the univariate or multivariate analyses (Tables\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e and \u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eSusceptibility of \u003cem\u003eA. baumannii\u003c/em\u003e isolates\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003en.52\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSensitive\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eResistance\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eResistance rate %\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMeropenem\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e90.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eImipenem\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e90.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAmikacin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e65.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGentamicin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e43\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e82.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eColistin (n.39)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e12.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTrimethoprim-sulfamethoxazole\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e43\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e82.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCiprofloxacin (n.17)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e76.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn our study, the 14-day mortality rate due to all causes was 26.9%, and the 28-day mortality rate was 42.3%. The mortality rates of patients with meningitis due to \u003cem\u003eA. baumannii\u003c/em\u003e vary between 15% and 71% [\u003cspan additionalcitationids=\"CR10 CR11\" citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Our results were similar to previous findings and emphasized the high mortality rates of these patients. Gram-negative bacterial meningitis has a high mortality rate, and managing this complex disease is challenging [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Besides the inability of antibiotics to cross the blood-brain barrier, the development of multi-drug resistance in microorganisms further aggravates the situation [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. \u003cem\u003eA. baumannii\u003c/em\u003e is a primary causative agent of gram-negative bacterial meningitis and is often associated with neurosurgical interventions [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. In our study, 48 (92.3%) of 52 meningitis patients affected by \u003cem\u003eA. baumannii\u003c/em\u003e had a history of neurosurgery. Our results were similar to those reported in other studies.\u003c/p\u003e \u003cp\u003eReducing the risk of death and increasing the recovery rates for patients suffering from meningitis caused by \u003cem\u003eA. baumannii\u003c/em\u003e is urgently required. Therefore, the risk factors affecting mortality need to be determined. However, conducting randomized controlled studies on this subject is difficult. Hence, retrospective studies and the analysis of real-life data are valuable. However, a few studies have investigated the factors affecting the outcome of meningitis caused by \u003cem\u003eA. baumannii\u003c/em\u003e. One of these is the study by Guardado et al., which examined the factors affecting treatment outcomes in 51 patients with \u003cem\u003eA. baumannii\u003c/em\u003e meningitis. In their study, advanced age and high leukocyte count in the CSF were associated with mortality. In the same study, five patients received intrathecal therapy only, 14 patients received a combination of intrathecal and IV therapy, and the others received IV therapy only. The difference in the mortality of the patients between treatments was not significant [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. Sharma et al. conducted a study with 72 patients. They found that being over 40 years old, having a GCS score below 8, having a CSF leucocyte count above 200, the presence of External Ventricular Drain (EVD), and the presence of comorbid diseases were the risk factors affecting mortality [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. In 2022, Zheng et al. investigated meningitis caused by non-fermentative Gram-negative bacteria, including A. baumannii, Pseudomonas aeruginosa, and Acinetobacter lwoffii. They reported that hypertension as a comorbid disease, the presence of an external ventricular drain (EVD), and the need for mechanical ventilation were independent risk factors for mortality [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn this study, we examined only patients with meningitis caused by \u003cem\u003eA. baumannii\u003c/em\u003e. We evaluated 15 factors by performing multivariate logistic regression analysis. The lack of IVT treatment was identified as an independent risk factor for mortality, increasing the risk of 14-day mortality by 5.6 times and 28-day mortality by 5.3 times.\u003c/p\u003e \u003cp\u003eThe blood procalcitonin levels before treatment were higher in deceased patients and statistically significant in the univariate analysis. However, in the regression analysis, it was not a significant risk factor for mortality. We did not find a significant difference between deceased and surviving patients regarding other variables examined, including the CSF leucocyte count, patient age, and predisposing disease for meningitis. This was different from the results of other studies. Such differences depend on the characteristics of the established cohort, the patient profile of the hospital where the study was conducted, the physical and medical facilities of the hospital, and other factors. Therefore, national and international multicenter studies on this subject need to be conducted.\u003c/p\u003e \u003cp\u003eOur results suggest that both IVT and IV treatments should be administered to patients with meningitis caused by \u003cem\u003eA. baumannii\u003c/em\u003e. The administration of IVT/ITH antibiotics makes the CSF sterile and reduces the required time to achieve it [\u003cspan additionalcitationids=\"CR19\" citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Our study showed significantly better microbiological responses in patients who received IVT treatment. It should be noted that the literature does not support the use of IVT/ITH therapy alone, and it is recommended that such therapy be avoided [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. In addition, we did not observe any chemical ventriculitis or catheter-related complications in patients receiving IVT treatment. Although we agree with the concerns about chemical meningitis reported in the literature, the absence of such complications in our case series underscores the safety of this treatment. Thus, we emphasize the necessity of adding IVT antibiotics to IV therapy.\u003c/p\u003e \u003cp\u003eThe Infectious Diseases Society of America's Clinical Practice Guidelines for Healthcare-Associated Ventriculitis and Meningitis (IDSA) recommends using colistimethate sodium or polymyxin B, both IV and IVT/ITH, for treating meningitis caused by carbapenem-resistant strains of \u003cem\u003eAcinetobacter\u003c/em\u003e species [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. In our study, colistin was administered to 21 patients, and amikacin was administered to five patients as IVT treatment. There was no significant difference in mortality rates between these groups. We suggest using amikacin as an IVT treatment for managing colistin-resistant strains, provided the strains are susceptible to amikacin.\u003c/p\u003e \u003cp\u003eIn our study, the antibiotic resistance rates were high in the investigated strains. The resistance rates for meropenem-imipenem, amikacin, and colistin were 90.4%, 65.4%, and 12.8%, respectively. Such high resistance rates were likely observed because our data spanned the last five years and included only A. baumannii strains. Antibiotic resistance is continuously increasing, and recent studies have reported similar resistance rates [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. High resistance rates pose significant challenges in selecting microbiologically active treatments [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. In our study, 31.9% of patients received inappropriate IV therapy. Although the appropriateness of therapy did not show a statistically significant impact on mortality, the mortality rate was lower in the group that received appropriate treatment. Our findings support a recent meta-analysis that suggests the difficulty of selecting appropriate IV antibiotic therapy in XDR gram-negative bacterial meningitis and highlights the potential mortality-reducing effect of IVT/ITH antibiotic administration.\u003c/p\u003e \u003cp\u003eOur study had some limitations. First, it is a retrospective study, and the quality of our filing system limits our results. Secondly, the study did not evaluate some factors that may affect the outcome, such as tumor grading, multiple catheterizations, blood transfusions, etc. Finally, therapeutic drug monitoring is not available in our unit. Therefore, it is not known how many patients have achieved the target drug concentration. However, our study has several strengths. It is one of the largest patient cohorts evaluating meningitis caused by \u003cem\u003eA. baumannii\u003c/em\u003e. This comprehensive study examined the patient's demographic characteristics, comorbidities, predisposing factors, laboratory results, and treatment options. Future studies should consider establishing a multicenter prospective cohort to evaluate other risk factors.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eMeningitis caused by \u003cem\u003eAcinetobacter baumannii\u003c/em\u003e is a disease with high mortality and is challenging to manage. Selecting the most effective treatment strategy is difficult because the pathogen must be sensitive to the antibiotic, and the selected drug must cross the blood-brain barrier. For patients with meningitis caused by \u003cem\u003eA. baumannii\u003c/em\u003e, IVT/ITH treatment is necessary. Our findings showed that adding IVT colistin or amikacin to IV therapy significantly decreases mortality. All centers should be encouraged to share their data regarding this matter, and prospective studies must be conducted to manage the disease.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eAll of the authors have seen and approved the manuscript. Currently, it has not been sent to any other journal for publication, and it has not been published elsewhere. We confirm that the manuscript complies with all instructions to authors provided by \u003cem\u003eNeurocritical Care\u003c/em\u003e. Artificial intelligence (AI)-assisted technology (ChatGPT) was used for language editing and writing refinement during the preparation of this manuscript. However, the study\u0026apos;s concept, research design, data analysis, interpretation of results, and discussion were entirely conducted by the authors without any AI assistance. We confirm no plagiarism in this manuscript, including text and images. All authors have reviewed and approved the final content to ensure accuracy, integrity, and originality.This study was approved by the Ethical Committee of Ondokuz Mayis University and by the Administrative Council of the Faculty of Medicine (Grant No.: 2022/426).\u003c/p\u003e\u003ch2\u003eFunding:\u003c/h2\u003e \u003cp\u003eThe authors declare that no funds, grants, or other support were received during the preparation of this manuscript.\u003c/p\u003e \u003cp\u003e \u003cb\u003eCompeting Interests\u003c/b\u003e: The authors have no relevant financial or non-financial interests to disclose.\u003c/p\u003e \u003cp\u003e\u003cb\u003eEthical Approval\u003c/b\u003e: This study was approved by the Ethical Committee of Ondokuz Mayis University and the Administrative Council of the Faculty of Medicine (Grant No.: 2022/426).\u003c/p\u003e \u003cp\u003e \u003cb\u003eSequence Information\u003c/b\u003e: Not applicable\u003c/p\u003e\u003ch2\u003eAuthor Contributions\u003c/h2\u003e \u003cp\u003eAll authors contributed to the study's conception and design. Fatih Temo\u0026ccedil;in, Tuba Kuruoglu, Aynur Atilla, S\u0026uuml;meyra Nur Erbaş, and Tuba Sena Kara\u0026ccedil;eşme performed material preparation, data collection, and analysis. Yeliz Tanriverdi \u0026Ccedil;aycı did the microbiological analysis. The first draft of the manuscript was written by Fatih Temo\u0026ccedil;in, Şevki Serhat Baydın, and Esra Tanyel, and all authors commented on previous versions. All authors read and approved the final manuscript.\u003c/p\u003e\u003ch2\u003eData availability\u003c/h2\u003e \u003cp\u003eThe datasets generated during and analyzed during the current study are not publicly available but are available from the corresponding author on reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eBargiacchi O, Rossati A, Car P, Brustia D, Brondolo R, Rosa F, et al. 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Multidrug-resistant \u003cem\u003eAcinetobacter\u003c/em\u003e meningitis in neurosurgical patients with intraventricular catheters: assessment of different treatments. \u003cem\u003eJ Antimicrob Chemother\u003c/em\u003e. 2008;61(4):908-13. doi:10.1093/jac/dkn018\u003c/li\u003e\n\u003cli\u003eSharma R, Goda R, Borkar SA, Katiyar V, Agarwal S, Kumar A, et al. Outcome following postneurosurgical \u003cem\u003eAcinetobacter\u003c/em\u003e meningitis: an institutional experience of 72 cases. \u003cem\u003eNeurosurg Focus\u003c/em\u003e. 2019;47(2):E8. doi:10.3171/2019.5.Focus19278\u003c/li\u003e\n\u003cli\u003eZheng G, Wang S, Lv H, Zhang G. 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Emergence of high colistin resistance in carbapenem resistant \u003cem\u003eAcinetobacter baumannii\u003c/em\u003e in Pakistan and its potential management through immunomodulatory effect of an extract from Saussurea lappa. \u003cem\u003eFront Pharmacol\u003c/em\u003e. 2022;13:986802. doi:10.3389/fphar.2022.986802\u003c/li\u003e\n\u003cli\u003eCafiso V, Stracquadanio S, Dovere V, Lo Verde F, Zega A, Pigola G, et al. Colistin Resistance Onset Strategies and Genomic Mosaicism in Clinical \u003cem\u003eAcinetobacter baumannii\u003c/em\u003e Lineages. \u003cem\u003ePathogens\u003c/em\u003e. 2021;10(11). doi: 10.3390/pathogens10111516\u003c/li\u003e\n\u003cli\u003eLi MT, Wu QQ, Li JB, Chen JS. Intrathecal or intraventricular antimicrobial therapy for post-neurosurgical Gram-negative bacillary meningitis or ventriculitis: a systematic review and meta-analysis. \u003cem\u003eInt J Antimicrob Agents\u003c/em\u003e. 2024 Jan;63(1):107033. doi: 10.1016/j.ijantimicag.2023.107033.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Acinetobacter baumannii, nosocomial meningitis, intraventricular treatment, intrathecal treatment, healthcare-associated meningitis","lastPublishedDoi":"10.21203/rs.3.rs-6165448/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6165448/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eIntroduction\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn this study, we analyzed the clinical features of nosocomial meningitis caused by \u003cem\u003eAcinetobacter baumannii\u003c/em\u003e (\u003cem\u003eA. baumannii\u003c/em\u003e) to identify the factors affecting the outcome and compared the effectiveness of different therapeutic regimens.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study analyzed patients diagnosed with healthcare-associated meningitis due to A. baumannii, and cases between 2017 and 2022 were included.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe analyzed data from 52 patients. The 14-day mortality rate was 26.9%, and the 28-day mortality rate was 42.3%. Univariate analysis of factors affecting mortality showed that patients who did not receive intraventricular (IVT) treatment had a 5.6-fold higher risk of 14-day mortality and a 5.3-fold higher risk of 28-day mortality. In these patients, the higher risk of 14-day and 28-day mortality was also confirmed by the results of the multivariate analysis [p = 0.032, OR: 15.341; p = 0.039, OR: 9.273, respectively]. Whereas 10 of 26 patients (38.4%) who received only intravenous (IV) treatment achieved microbiological cure, 20 of 26 patients (76.9%) who received IV + IVT treatment achieved microbiological cure, and the difference was statistically significant (p = 0.005). There were no differences in 14-day and 28-day mortality rates between patients who received IVT colistin or amikacin in addition to IV therapy (p = 0.51, p = 0.63, respectively).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eOur findings showed that adding IVT colistin or amikacin to IV therapy significantly decreases mortality and increases the microbiological cure.\u003c/p\u003e","manuscriptTitle":"Meningitis Caused by Extensively Drug-Resistant Acinetobacter baumannii: Treatment Options and Factors Affecting Outcomes","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-03-31 10:09:46","doi":"10.21203/rs.3.rs-6165448/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"44e23fe4-663f-4fd2-8b22-dd9566109e2a","owner":[],"postedDate":"March 31st, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-05-02T15:17:56+00:00","versionOfRecord":[],"versionCreatedAt":"2025-03-31 10:09:46","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6165448","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6165448","identity":"rs-6165448","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}